I recently picked up some Agfa Fix-AG which I've not used before. The dilutions listed on the bottle for FB paper fixing are 1:7 and 1:9 The respective times for these dilutions are 1-3 minutes and 3-5 minutes.

I would love to be able to use it at 1:7 for 1 minute fixing time to minimise fixer retention and wash times but can anyone verify this is Ok. Should I just go with the standard 1:4 dilution if I want short fixing times?